Electronic calculators
carry out the calculations asked of them to a higher degree of accuracy
than they give in their display. Some calculators round their answer
to the number of places available in the display, while others just
ignore the digits at the end when the display is full without rounding.
This process of cutting off the tail is called truncating.

Try dividing
2 by 3 using your calculator. If the last figure in the display
is 7 then it is rounding the answer, if it is 6 then it is truncating.